I hope you get it mounted soon and have some calm spring days to cruise and look.
Get an SD card so you can capture routes (tracks) and waypoints to the card. Turn on screen
Shot capture (when active, it will save a screenshot every time you mark a waypoint.
Download free Humviewer onto your computer. You can then view your tracks and waypoints later, from the SD card, on the larger computer screen, with some image enhancement views Humviewer provides, including separating the display into different windows with different colors, different mode views (SI, DI, 2D) and even compare some views of same spot with 80 vs 200 or 455 sounding. You will see things that you just can't see on the small screen, in the sun, with some glare, moving around, holding a rod, eating a sandwich, running the boat, netting fish for Charger or Cannonball, adjusting your bifocals. Believe me, it is amazing. You'll be happy with the 698 and even happier when you use Humviewer to study what it sees. There are other viewers but I can't advise about them.
Here are some interesting views from my 598. Good luck and enjoy your new toy!
Shallow water dock showing verticals and cross structures:
Big school of fish show 50-75' left on side imaging:
Submerged road and bridge:
Other views of that bridge:
Caught lots of crappie here.
Winter crappie bunched up in the creek bottom. Compare 2D vs Down Image: